SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8550628cc4810b0a403115ccd6dd981004f43fcf565278db0219bca414fc35de' 
  AND token = 'XQT5Ojvj3XOBLcCNNKQpwyNyG2vLHYQFtZTzfe0kh7k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}